Find every subdomain
of a domain.

Every hostname under a domain that ever appeared in a public TLS certificate — with certificate counts, first/last seen and live DNS status.

5 hosts · 244 ms

HostCertsFirst seenLast seenDNS
sparkasse-passau.de 1 2026-04-23 2026-04-23 ok
psd2-xs2a.sparkasse-passau.de 2 2025-08-11 2026-07-01 nxdomain
module.sparkasse-passau.de 1 2026-04-23 2026-04-23 ok
mailing.sparkasse-passau.de 5 2026-04-22 2026-08-19 ok
www.sparkasse-passau.de 1 2026-04-23 2026-04-23 ok

Programmatic access, with DNS A records: API GET /v1/hosts/sparkasse-passau.de (API key for paging).

Shown here: hostnames with a certificate that is valid now or expired within the last 90 days. The full history since 2013 — hostnames whose last certificate expired earlier — is a Pro plan method: GET /v1/hosts-history/sparkasse-passau.de.